How To Coax A Yeast To Ferment A 12%ABV Beer Down To 14%ABV?

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Die Schwarzbier Polizei
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Gentlemen, I have a question on how to coax a yeast to ferment a 12%ABV beer down to 14%ABV?

On December 06 I brewed a Hürlimanns Samichlaus clone, OG 1.130. I fermented it in primary for 45 days, as recipe suggested, at slowly increasing temperature with staggered additions of Glucose. The yeast is Saflager S-189, full cake from the previous light batch, brewed specifically for that purpose.

Today, the primary's over: 1.038 SG / 12% ABV / 70% Attenuation instead of the 1.023 SG / 14% ABV / 80% Att. in the recipe. Which is an obvious underattenuanon (though the beer tastes awsome).

From various sources I learned that Hürlimann additionally fermented their Samichlaus with one more strain - a Champaign one. I don't have a Champaigne yeast but I think it could be substituted with a Diastaticus Belgian yeast (which are believed to be genetically close to the Champaigne) - like Belgian Ale M41, f. ex.

Before I pitch M41 for the secondary fermentation, I'd like to ask, what do you think, is it feasible at all, to make a yeast (albeit a Diastaticus and with a lot of remaining fermentables) to work in an environment already at the limit of its stated Alcohol Tolerance of 12%? Is it possible somehow to coax it into fermentation?
Probably, make a starter and pitch at the High Kräusen?
 
The beer tastes awesome? I'd quit now and start drinking!
:mug:
But if you want to experiment, siphon off a gallon or so and pitch your other yeast. Then if it doesn't work out, you haven't wasted all of your awesome tasting beer
Is there a chance you mashed on the high side and that's why it stopped at 1.038? Any nutrients used?
 
The beer tastes awesome? I'd quit now and start drinking!
That sounds wise! I'm thinking of fermenting even lower only because I'm decided to follow the original recipe to a tee. Including 6 to 8 months lagering, after the fermentation is done.
No nutrients, just staggered Glucose additions and lots of clean (hops strained) trub. It was a decoction mash, so very fermentable wort.
I think the critters dropped off just because they'd reached past the limit of their alcohol tolerance, which is stated by the manufacturer at 11%.
 
keg it and let it sit a few months to age. Might drop some more as it ages.
 
Pull off a Mason jar of wort to experiment on. Sometimes adding a different, less tired yeast will finish things up a bit further. You mentioned Champagne yeast there are differing beliefs there whether it can finish it out due to limited ability to ferment maltose and not maltotriose at all. I say toss it in, why not.

Also toss in any other highly attenuating yeasts you have from your yeast vault. US-05 comes to mind. Also, I was experimenting with finishing higher ABV with viciously hungry Hornindal Kviek, it was good for a couple points last I checked. Toss it in.

Finally, you can find alpha amylase powder at the local homebrew shop. That will continue to break up the wort a bit. Even crushed Beano will help. Toss ‘em in.

If your Mason jar experiment works, scale it up for the main batch… Prost!
 
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if you get a turbo yeast pack, ferment some sugar with it, then collect the yeast, maybe do another ferment with it to clean the crap tasting nutrients off more...then pitch that it would possibly drop it down to 1.014...turbo yeast are good to 16%, IME, the nutrients they use to make them 'turbo' taste horrible though...
 
I think it’s difficult to pull this off at this stage. I‘d make a 1.130 starter with champagne yeast and pitch it when it gets down to 1.040, reaches about 12%. Then cross your fingers.
 
Thank you all for your suggestions! So much of them and each one is helpful!
What I finally did, was checking manufacturer's datasheets for each yeast in my fridge. I found that Lalbrew Belle Saison had Alcohol Tolerance up to 15%, so I hope it's not impossible to make it work at 12% ABV. Also I found a post on this Board, where a guy used Belle Saison to solve the same problem and succeeded. Most importantly, he reported he didn't notice any Saisony flavour contribution after secondary fermentation of such a low-sugar wort. So, I just made a small Belle Saison starter and when the Kräusen is at its Highest, I'll pitch it.
 
I did that to a chocolate stout that finished at 1.034. The Yeast Bay dry Belgian,pitched at high krausen in the keg. It finished at 1.012 and tasted terrible, all the chocolate flavor was replaced with phenolic belgianess. It was totally drinkable at 1.034 and I'll never do that again. Ended up running it thru a purifier so it didn't go to waste.
 
Listened to a podcast yesterday, talking to someone that made Imperials of all sorts, and they mentioned as fermentation started to slow that they'd continuously add a little more sugar, and that the fermentation would keep on going. Said the Chico strain would hit up to 14% that way. Might be something to consider if you can think of how to do it in a sanitary way (they didn't get into that).
 
I’ve often suspected that when you order a flight of beers at your local brewery restaurant, the one they call “Belgian” is really from their phenolic beer failure vat. That’s where the failed batches go.

They sell it to you one sampler at a time to get rid of it!
D417BC0E-A822-4C47-8690-7EB12765C995.jpeg
 
as fermentation started to slow that they'd continuously add a little more sugar, and that the fermentation would keep on going
That's what I did. There was 6% of Glucose in the recipe, I added it in small staggered doses at the 7th, 14th and 18th days of fermentation. Each time it reinvigorated fermentation visibly, and still I got underattenuation - exactly when the Alcohol Tolerance of the yeast had been reached.

It finished at 1.012 and tasted terrible
Oh no... That's what I'm afraid of. Aside from being chewy and slicky, this 1038-FG beer tastes awsome. It would be a shame to ruin it with phenols. I hoped Saison yeast won't be detectable, as it was the case in the above mentioned post. I also speculated that Belle Saison was the least pungent of all four dry Saison strains (Belle, M29, M31 and BE-134), in my experience. And now your report comes...
 
Interesting, I just read that at very high gravity maltose (therefore DME presumably) can be more fermentable than glucose for lager yeast. I wonder if it’s worth adding a DME paste? No need to sanitise it, as the high ethanol level is going to take care of any undesirable bugs. Maybe pull some for an experiment, as @Beermeister32 suggests.
 
Each time it reinvigorated fermentation visibly, and still I got underattenuation -


you need to keep in mind there's about 1 vol co2 in solution from fermentation....you can add just about anything to wort, and it will seem like fermentation took off vigorusly for about 2-3 minutes.....
 
i think that would increase both ABV 'and' FG though? are you looking for dryer beer, or just 14%ABV?
That’s a very good point. I think I might have been thinking more about replacing late staggered glucose additions, tbh.
 
it will seem like fermentation took off vigorusly
Sure it will! I'm aware of the difference between fermentation and degassing. I'm not such a n00by n00b as I probably look with this my question :D The Samichlaus in question was my 201st batch

are you looking for dryer beer, or just 14%ABV?
To be exact, I'm looking for attenuation of 80%. It's a thoroughly followed recipe, and I managed to tick all the boxes except the lower-than-expected attenuation. And even that wasn't unexpected, as the stated Alcohol Tolerance of S-189 yeast is 11%ABV, while the recipe requires 14%. I knew that Hürlimanns somehow managed to coax this exactly yeast (Zürich Lager) into such a high attenuation. I just didn't know their technique. I hoped someone could give an advise on that. But now, exploring the subject in the intertwebz, I see that Hürlimanns employed some precisely dosed Oxygenation of the fermenting Wort. Which is unfortunately unavailable to me. So, the only mean remaining to me is addition of Diastatic Alcohol-tolerant yeast. Which I'm not exactly happy with, as it might shift the flavour (which is already awesome).

No Syrup or Extract additions are possible at his stage, as all the simple sugars prescribed by the recipe have been already added.
 
I'm not such a n00by n00b as I probably look with this my question :D


wait? no one has asked if your using a refractometer for this reading? ;) :mug:

edit: honestly? i'm wondering what came in your stocking now? was it a refrac? i punched the recipie for that into beersmith, and it predicts a FG of 1.008? with one addition of 1lb candi sugar? and you say you added multiple additions? and a corrected FG with a refrac would be like a brix of 9, and fg of actually .989 or something like that, which would make sense?

at least this is what i entered...

https://www.homebrewersassociation.org/homebrew-recipe/falconclaws-samichlaus/
 
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wait? no one has asked if your using a refractometer for this reading? ;) :mug:
Even more than that! No one has told me yet that the lack of Bubbles in the Bubbler doesn't equate to a stuck fermentation! 🤣

at least this is what i entered...
Yes, I've seen that recipe. It's a good one: just 5 malts instead of usually suggested 24 and no silly things like Special B in a Germanic beer. However I preferred the BYO version (3 malts), slightly altered on the base of bits of information from the manufacturer I had found around the web.

The beer should be 1.130 OG (all later Sugar additions included, it goes into the fermenter at a lower gravity) and no higher than 1.023 FG at 80% Attenuation, measured with a nice glass SG-scale hydrometer (no wildly uncalibrated refracts in my stocking this Xmas 😭). I use BeerSmith only for calculating my dry-hopped recipes (which I brew rarely), so I calculated the recipe in a rare discontinued offline PC version of Brewer's Friend, which I love and which gives just negligibly different calculations than BeerSmith.
 
and which gives just negligibly different calculations than BeerSmith.


yeah, that was a case of me being a double *******.....i forgot beersmith defaults to extract...

at this point, i have to side with the....if it tastes good don't try and fix it if it ain't broke crowd....
 
Probably, the "don't fix" approach might be the best one.
I think I won't be adding Saison yeast to not ruin the awesome flavour (will use up the starter in a crazy Peated Rye Saison project instead) and keep my Samichlaus in a warm place for a couple of weeks, hoping it drops some degrees more. And then to Lagering.
 
i've tried 'saving' a lot of batches, it never works
Yep. I'd better avoid that familiar regretful feeling when I pour down-the-gurgler a "rescued" batch that otherwise would be a decent beer if I hadn't messed with it. It happened before. No more.

I have finally decided what I'll do: I'll make a massive starter of the same S-189 yeast, pitch it at the High Kräusen and keep warm, much warmer than the original fermentation temperature (Zürich Lager is a warm-tolerant strain anyway). If it does ferment down a little bit more until it drowns in Alcohol, then good. If not, let the beer stays as it is. It's already very good and tasty.
 
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